Top answers

Describe the formation of a waterfall?

Waterfalls form where there is a layer of hard rock on top of a layer of soft rock. The soft rock is eroded more quickly and undercuts the hard rock creating a ledge. The overhanging ledge is unsupported and...
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Answered by Emily B. • Geography tutor
4095 Views

describe the electrostatic force between water molecules

a type of wander waals force called hydrogen bonding due to the slightly positive hydrogens and slightly negative oxygen. this occurs because of the uneven attraction for electrons between the oxygen and hyd...
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Answered by Murray S. • Chemistry tutor
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How does fractional distillation separate different hydrocarbons in crude oil?

Crude oil is a mixture of different hydrocarbons, which all have different lengths and must be separated by length into different useful 'fractions'. Fractional distillation achieves this by using the fact t...
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Answered by Samuel J. • Chemistry tutor
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If cells can respire anaerobically, why do humans need oxygen?

Cells can indeed respire - or release energy - without oxygen, using anaerobic respiration. Here, energy is released from glucose to generate a substance called lactic acid. This is a good temporary solution...
SJ
Answered by Samuel J. • Biology tutor
26392 Views

Describe the primary and secondary effects of an earthquake.

One common primary (or immediate) effect of an earthquake is the destruction of buildings. The collapse of buildings could in turn lead to the loss of life. Earthquakes may also cause damage to vital infrast...
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Answered by Sam W. • Geography tutor
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